1. Field of the Invention
This invention relates to a buckle for joining the ends of three belts, and more particularly to a buckle comprising a pair of male members adapted for fastening one end of each one of first and second belts, and a female member for retaining the pair of male members and adapted for fastening one end of a third belt.
2. Description of the Prior Art
Prior-art buckles for joining the ends of three belts include, for example, the belt connecter taught by Japanese Utility Model Public Disclosure Sho 61-147012, and the buckle device taught by Japanese Patent Public Disclosure Hei 6-284916.
The belt connector disclosed in Utility Model Public Disclosure Sho 61-147012 comprises a case connected with one belt and inserts connected with the other belts. A plate spring is provided inside the case for clamping the inserted inserts between the plate spring itself and the case, and an operating member is provided upon the front surface of the case for releasing the engagement between the inserts and the case by flexing the plate spring away from the inserts so as to separate the inserts from the plate spring.
The buckle device disclosed in Japanese Patent Public Disclosure Hei 6-284916 comprises a buckle body and a pair of tongue plates. Each one of a pair of engaging members provided inside the buckle body is spring biased to independently engage one of the tongue plates. The front of the buckle body is provided with a button plate movably supported on a base member of the buckle body so as to enable release of the tongue plates by pressing down on the button plate so as to press down on and move the pair of engaging members.
Since the aforementioned belt connector joins the belts by clamping the inserts between the plate spring and the case, release of the engagement requires the plate spring to be moved about a pivot point between the plate spring and the case. In order to render the belt connector of this configuration easy to use, the case has to be of a flat or thin box-like shape and, as shown in FIG. 1 of Utility Model Public Disclosure Sho 61-147012, the plate spring has to be pivotably fastened to one side of the case with its distal end located on the front side of the case. As a result, the release of the engagement has to be achieved by use of an arrangement having an operating member linked with the plate spring in a such manner that the plate spring is pressed away from the front of the case toward the back thereof when the operating member is pressed inward.
The aforesaid buckle device similarly requires the engaging members, for releasing the engagement of the tongue plates, to be pivotably fastened to one side of the buckle body with their distal ends located on the front side of the buckle body. As a result, the release of the engagement has to be achieved by use of an arrangement in which the engaging members are pressed away from the front of the case toward the back thereof by means of the button plate when the button plate is pressed inward.
When a belt connector or the like of this type is used for joining belts to secure a person in a seat or the like, the rear surface of the main body of the belt connector comes in contact with the abdomen of the wearer. When the operating member or the like is pressed inward from the front of the main body toward the rear thereof in order to release the belts, therefore, the belt wearer experiences pressure on the abdomen. This is particularly a problem when a belt connector of this type is used for securing a baby or small child in a stroller, vehicle child seat or the like because the pressure exerted on the abdomen when the operating member is pressed inward causes the baby or child considerable discomfort. An improved belt connector has therefore been desired.
Moreover, since the rear surface of a belt connector of this type comes into contact with a soft region of the wearer's abdomen, the pressure applied to the operating member or the like often causes the belt connector as a whole to sink into the wearer's abdomen. As a result, smooth disengagement is frequently hindered due to the fact that the pressure conveyed to the plate spring from the operating member is not sufficient to elastically deform the plate spring to the point necessary for releasing the engagement between the inserts or the like and the plate spring elastically engaged therewith.
Because of this, the disengagement sometimes has to be achieved by, for example, inserting one or more fingers between the wearer's abdomen and the case of the belt connector and squeezing the case from both sides.
Moreover, since the distal end of the operating member used to depress the pivoted plate spring swings along an arc centered on the pivot point between the case and the plate spring, the operating member cannot be pushed straight toward the rear of the case. This makes it hard to press the operating member in smoothly.